A method for efficiently leaching valuable metals from waste NCM111 type lithium ion battery cathode material

Abstract

The present application relates to a kind of from waste NCM111 type lithium ion battery cathode material high-efficiency leaching valuable metal method, belong to the recycling technology field of waste lithium battery.The present application is with DL-malic acid as hydrogen bond donor, betaine hydrochloride is hydrogen bond acceptor, at temperature 60~90 ℃, betaine hydrochloride and DL-malic acid are uniformly mixed and deionized water is stirred to generate colorless transparent deep eutectic solvent;Waste LNCM type lithium ion battery cathode material is crushed, screening is obtained waste battery cathode powder, waste lithium ion battery cathode material is added to deep eutectic solvent, at temperature 70~90 ℃, stirring leaching 40~60 min obtains valuable metal leaching solution.The present application utilizes the deep eutectic solvent from waste ternary lithium ion battery cathode material leaching lithium manganese cobalt nickel, and the leaching rate under optimal condition can be as high as 99% or more.

Description

Technical Field

[0001] This invention relates to a method for efficiently leaching valuable metals from the cathode material of waste NCM111 lithium-ion batteries, belonging to the field of waste lithium battery recycling technology. Background Technology

[0002] Currently, the main methods for recycling spent lithium-ion batteries include pyrometallurgy, hydrometallurgy, and direct recycling. Pyrometallurgy achieves metal recovery through high-temperature smelting. Although the process is simple and the recovery rate is high, it has disadvantages such as high energy consumption, easy generation of harmful gases, low metal purity, and inability to be directly used for electrode manufacturing, resulting in a significant environmental burden. Hydrometallurgy, on the other hand, is based on the leaching of valuable metals with chemical solvents. It has advantages such as low energy consumption, high metal recovery rate, and greater flexibility. However, it usually uses strong acids and alkalis, which severely corrode equipment, has a long process flow, and may generate a large amount of waste liquid, posing a risk of secondary pollution. Furthermore, it still faces difficulties in separating elements with similar properties.

[0003] In summary, current pyrometallurgical and hydrometallurgical methods still have significant limitations in terms of economic efficiency, environmental sustainability, and technological effectiveness. While direct recycling technology can directly regenerate materials by repairing the cathode crystal structure, reducing energy consumption and waste, and is considered a more attractive green approach, it has not yet been widely applied due to issues such as high chemical sensitivity to input materials and unstable quality of recycled materials. Therefore, developing an efficient, mild, environmentally friendly, and economically feasible recycling process has become an urgent need for the resource recycling of lithium-ion batteries. Summary of the Invention

[0004] To address the problems of harsh reaction conditions, low leaching rates, and the presence of difficult-to-degrade and toxic solvents in current leaching processes for lithium-ion battery cathode materials, this invention proposes a method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode materials. A deep eutectic solvent is prepared using DL-malic acid as a hydrogen bond donor and betaine hydrochloride as a hydrogen bond acceptor. This deep eutectic solvent is used to leach lithium, nickel, cobalt, and manganese from waste LNCM lithium-ion battery cathode materials, reducing the leaching time to less than 50 minutes, with leaching efficiencies for lithium, nickel, cobalt, and manganese all exceeding 99%. This process is characterized by low cost, rapid efficiency, and environmental friendliness, effectively reducing the recycling costs of waste ternary lithium battery cathode materials.

[0005] A method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode material, the specific steps of which are as follows: (1) Using DL-malic acid as a hydrogen bond donor and betaine hydrochloride as a hydrogen bond acceptor, DL-malic acid and betaine hydrochloride were mixed evenly and dissolved in deionized water at a temperature of 60~90℃, and cooled to room temperature to obtain a deep eutectic solvent. (2) Waste LNCM type lithium-ion battery cathode material is crushed and screened to obtain waste battery cathode powder. The waste battery cathode powder is added to a deep eutectic solvent and leached at a temperature of 70~90℃ for 40~60min to obtain lithium nickel cobalt manganese leaching solution.

[0006] Preferably, in step (1), the molar ratio of betaine hydrochloride to DL-malic acid is 2:1 to 1:3.

[0007] Preferably, the deionized water content in the deep eutectic solvent in step (1) is 30-50% by mass.

[0008] Preferably, the particle size of the waste battery positive electrode powder in step (2) is 5~15μm.

[0009] Preferably, in step (2), the solid-liquid ratio g:L of the waste battery positive electrode powder and the deep eutectic solvent is 20~50:1.

[0010] The leaching rates of Ni, Co, Mn, and Li in the cathode material of waste LNCM type lithium-ion batteries are calculated using the following formulas: η=[(C Me ×V) / (w Me [×m)]×100%, In the formula, C Me The concentration (mg / L) of metal ions (Me = Li, Ni, Co, Mn) in the leachate, V is the volume of the leachate (L), and m is the mass (g) of the cathode active material; w Me This represents the mass fraction (wt%) of the metal in the cathode active material.

[0011] This invention utilizes the principle of leaching Ni, Co, Mn, and Li from waste LNCM-type lithium-ion battery cathode materials using a deep eutectic solvent: (1) In the deep eutectic solvent, the hydrogen ions ionized from DL-malic acid combine with the oxygen in the metal-oxygen bond of the cathode material to generate water, which leads to the destruction of the layered structure of the cathode material and promotes the release of metal ions. (2) Ni in cathode materials 3+ Co 3+ Mn 4+ High-valence metal ions are reduced to Ni 2+ Co 2+ Mn 2+ Low-valence metal ions; (3) The reduced low-valence metal ions form complexes with chloride ions in betaine hydrochloride. Due to the presence of water, some of the chloride complexes are hydrolyzed to generate complexes of hydrated metal ions, which eventually lead to coordination equilibrium between the complexes of chloride metal ions and the complexes of hydrated metal ions.

[0012] The beneficial effects of this invention are: (1) In this invention, DL-malic acid is used as a hydrogen bond donor and betaine hydrochloride is used as a hydrogen bond acceptor to prepare a deep eutectic solvent. The deep eutectic solvent is used to leach lithium, nickel, cobalt and manganese in waste LNCM type lithium-ion battery cathode materials, which can shorten the leaching time to less than 50 minutes. The leaching efficiency of lithium, nickel, cobalt and manganese is all above 99%. (2) The present invention uses deep eutectic solvent to leach lithium nickel cobalt manganese in waste LNCM type lithium-ion battery cathode material, avoiding the use of toxic solvents, strong acids, strong alkalis and reducing agents, and the DL-malic acid and betaine hydrochloride can be naturally degraded, reducing the harm to the environment. (3) The process of the present invention is simple to operate, has a low reaction temperature, a short leaching time and extremely high leaching efficiency throughout the leaching process. Detailed Implementation

[0013] The present invention will be further described in detail below with reference to specific embodiments, but the scope of protection of the present invention is not limited to the content described.

[0014] In this embodiment of the invention, the waste NCM111 lithium-ion battery cathode material contains 7.2% Li, 19.8% Ni, 20.0% Co and 18.5% Mn by mass percentage.

[0015] Example 1: A method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode material, the specific steps of which are as follows: (1) Using DL-malic acid as a hydrogen bond donor and betaine hydrochloride as a hydrogen bond acceptor, DL-malic acid and betaine hydrochloride were mixed evenly and dissolved in deionized water at a temperature of 60°C and a stirring speed of 600 rpm, and then cooled to room temperature to obtain a deep eutectic solvent; the molar ratio of betaine hydrochloride to DL-malic acid was 1:2; the mass content of deionized water in the deep eutectic solvent was 30%; (2) Waste LNCM type lithium-ion battery cathode material is crushed and screened to obtain waste battery cathode powder with an average particle size of 10μm. The waste battery cathode powder is added to a deep eutectic solvent and leached at 90℃ for 50min to obtain lithium nickel cobalt manganese leaching solution. The solid-liquid ratio of the waste battery cathode powder to the deep eutectic solvent is 40:1 (g:L). The contents of Ni, Co, Mn and Li in the lithium nickel cobalt manganese leaching solution were determined using inductively coupled plasma atomic emission spectrometry. The leaching rates of Ni, Co, Mn and Li in this embodiment were calculated to be 99.70%, 97.78%, 99.08% and 99.81%, respectively.

[0016] Example 2: A method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode material, the specific steps of which are as follows: (1) Using DL-malic acid as a hydrogen bond donor and betaine hydrochloride as a hydrogen bond acceptor, DL-malic acid and betaine hydrochloride were mixed evenly and dissolved in deionized water at a temperature of 70°C and a stirring speed of 500 rpm, and then cooled to room temperature to obtain a deep eutectic solvent; the molar ratio of betaine hydrochloride to DL-malic acid was 1:2; the mass content of deionized water in the deep eutectic solvent was 30%; (2) Waste LNCM type lithium-ion battery cathode material is crushed and screened to obtain waste battery cathode powder with an average particle size of 10μm. The waste battery cathode powder is added to a deep eutectic solvent and leached at 80℃ for 50min to obtain lithium nickel cobalt manganese leaching solution. The solid-liquid ratio g:L of the waste battery cathode powder to the deep eutectic solvent is 30:1. The contents of Ni, Co, Mn and Li in the lithium nickel cobalt manganese leaching solution were determined using inductively coupled plasma atomic emission spectrometry. The leaching rates of Ni, Co, Mn and Li in this embodiment were calculated to be 98.92%, 96.64%, 97.58% and 98.73%, respectively.

[0017] Example 3: A method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode material, the specific steps of which are as follows: (1) Using DL-malic acid as a hydrogen bond donor and betaine hydrochloride as a hydrogen bond acceptor, DL-malic acid and betaine hydrochloride were mixed evenly and dissolved in deionized water at a temperature of 90°C and a stirring speed of 700 rpm, and then cooled to room temperature to obtain a deep eutectic solvent; the molar ratio of betaine hydrochloride to DL-malic acid was 1:3; the mass content of deionized water in the deep eutectic solvent was 40%; (2) Waste LNCM type lithium-ion battery cathode material is crushed and screened to obtain waste battery cathode powder with an average particle size of 10μm. The waste battery cathode powder is added to a deep eutectic solvent and leached at 90℃ for 40min to obtain lithium nickel cobalt manganese leaching solution. The solid-liquid ratio g:L of the waste battery cathode powder and the deep eutectic solvent is 40:1. The contents of Ni, Co, Mn and Li in the lithium nickel cobalt manganese leaching solution were determined using inductively coupled plasma atomic emission spectrometry. The leaching rates of Ni, Co, Mn and Li in this embodiment were calculated to be 93.05%, 89.27%, 91.21% and 92.88%, respectively.

[0018] Example 4: A method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode material, the specific steps of which are as follows: (1) Using DL-malic acid as a hydrogen bond donor and betaine hydrochloride as a hydrogen bond acceptor, DL-malic acid and betaine hydrochloride were mixed evenly and dissolved in deionized water at a temperature of 60°C and a stirring speed of 600 rpm, and then cooled to room temperature to obtain a deep eutectic solvent; the molar ratio of betaine hydrochloride to DL-malic acid was 1:1; the mass content of deionized water in the deep eutectic solvent was 40%; (2) Waste LNCM type lithium-ion battery cathode material is crushed and screened to obtain waste battery cathode powder with an average particle size of 10μm. The waste battery cathode powder is added to a deep eutectic solvent and leached at 90℃ for 40min to obtain lithium nickel cobalt manganese leaching solution. The solid-liquid ratio g:L of the waste battery cathode powder and the deep eutectic solvent is 40:1. The contents of Ni, Co, Mn and Li in the lithium nickel cobalt manganese leaching solution were determined using inductively coupled plasma atomic emission spectrometry. The leaching rates of Ni, Co, Mn and Li in this embodiment were calculated to be 92.51%, 88.57%, 90.54% and 92.38%, respectively.

[0019] Example 5: A method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode material, the specific steps of which are as follows: (1) Using DL-malic acid as a hydrogen bond donor and betaine hydrochloride as a hydrogen bond acceptor, DL-malic acid and betaine hydrochloride were mixed evenly and dissolved in deionized water at a temperature of 80°C and a stirring speed of 600 rpm, and then cooled to room temperature to obtain a deep eutectic solvent; the molar ratio of betaine hydrochloride to DL-malic acid was 1:3; the mass content of deionized water in the deep eutectic solvent was 50%; (2) Waste LNCM type lithium-ion battery cathode material is crushed and screened to obtain waste battery cathode powder with an average particle size of 10μm. The waste battery cathode powder is added to a deep eutectic solvent and leached at 80℃ for 50min to obtain lithium nickel cobalt manganese leaching solution. The solid-liquid ratio of the waste battery cathode powder to the deep eutectic solvent is 40:1 (g:L). The contents of Ni, Co, Mn and Li in the lithium nickel cobalt manganese leaching solution were determined using inductively coupled plasma atomic emission spectrometry. The leaching rates of Ni, Co, Mn and Li in this embodiment were calculated to be 92.54%, 88.86%, 90.82% and 92.41%, respectively.

[0020] Example 6: A method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode material, the specific steps of which are as follows: (1) Using DL-malic acid as a hydrogen bond donor and betaine hydrochloride as a hydrogen bond acceptor, DL-malic acid and betaine hydrochloride were mixed evenly and dissolved in deionized water at a temperature of 80°C and a stirring rate of rpm, and then cooled to room temperature to obtain a deep eutectic solvent; the molar ratio of betaine hydrochloride to DL-malic acid was 2:1; the mass content of deionized water in the deep eutectic solvent was 30%; (2) Waste LNCM type lithium-ion battery cathode material is crushed and screened to obtain waste battery cathode powder with an average particle size of 10μm. The waste battery cathode powder is added to a deep eutectic solvent and leached at 80℃ for 60min to obtain lithium nickel cobalt manganese leaching solution. The solid-liquid ratio of the waste battery cathode powder to the deep eutectic solvent is 50:1 (g:L). The contents of Ni, Co, Mn and Li in the lithium nickel cobalt manganese leaching solution were determined using inductively coupled plasma atomic emission spectrometry. The leaching rates of Ni, Co, Mn and Li in this embodiment were calculated to be 86.62%, 83.67%, 84.32% and 87.27%, respectively.

[0021] Example 7: A method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode material, the specific steps of which are as follows: (1) Using DL-malic acid as a hydrogen bond donor and betaine hydrochloride as a hydrogen bond acceptor, DL-malic acid and betaine hydrochloride were mixed evenly and dissolved in deionized water at a temperature of 60°C and a stirring speed of 600 rpm, and then cooled to room temperature to obtain a deep eutectic solvent; the molar ratio of betaine hydrochloride to DL-malic acid was 1:2; the mass content of deionized water in the deep eutectic solvent was 30%; (2) Waste LNCM type lithium-ion battery cathode material is crushed and screened to obtain waste battery cathode powder with an average particle size of 10μm. The waste battery cathode powder is added to a deep eutectic solvent and leached at 90℃ for 40min to obtain lithium nickel cobalt manganese leaching solution. The solid-liquid ratio g:L of the waste battery cathode powder and the deep eutectic solvent is 30:1. The contents of Ni, Co, Mn and Li in the lithium nickel cobalt manganese leaching solution were determined using inductively coupled plasma atomic emission spectrometry. The leaching rates of Ni, Co, Mn and Li in this embodiment were calculated to be 99.38%, 97.34%, 98.26% and 99.61%, respectively.

[0022] Example 8: A method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode material, the specific steps of which are as follows: (1) Using DL-malic acid as a hydrogen bond donor and betaine hydrochloride as a hydrogen bond acceptor, DL-malic acid and betaine hydrochloride were mixed evenly and dissolved in deionized water at a temperature of 60°C and a stirring speed of 600 rpm, and then cooled to room temperature to obtain a deep eutectic solvent; the molar ratio of betaine hydrochloride to DL-malic acid was 1:1; the mass content of deionized water in the deep eutectic solvent was 30%; (2) Waste LNCM type lithium-ion battery cathode material is crushed and screened to obtain waste battery cathode powder with an average particle size of 10μm. The waste battery cathode powder is added to a deep eutectic solvent and leached at 70℃ for 60min to obtain lithium nickel cobalt manganese leaching solution. The solid-liquid ratio g:L of the waste battery cathode powder and the deep eutectic solvent is 30:1. The contents of Ni, Co, Mn and Li in the lithium nickel cobalt manganese leaching solution were determined using inductively coupled plasma atomic emission spectrometry. The leaching rates of Ni, Co, Mn and Li in this embodiment were calculated to be 89.48%, 90.35%, 91.14% and 92.81%, respectively.

[0023] The specific embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode material, characterized in that, The specific steps are as follows: (1) Using DL-malic acid as a hydrogen bond acceptor and betaine hydrochloride as a hydrogen bond donor, DL-malic acid and betaine hydrochloride were mixed evenly and dissolved in deionized water at a temperature of 60~90℃, and cooled to room temperature to obtain a deep eutectic solvent. (2) Waste LNCM type lithium-ion battery cathode material is crushed and screened to obtain waste battery cathode powder. The waste battery cathode powder is added to a deep eutectic solvent and leached at a temperature of 70~90℃ for 40~60min to obtain lithium nickel cobalt manganese leaching solution.

2. The method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode material according to claim 1, characterized in that: Step (1) The molar ratio of betaine hydrochloride and DL-malic acid is 2:1 to 1:

3.

3. The method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode material according to claim 1, characterized in that: Step (1) The deionized water content in the deep eutectic solvent is 30-50%.

4. The method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode material according to claim 1, characterized in that: Step (2) The particle size of the positive electrode powder of the waste battery is 5~15μm.

5. The method for efficiently leaching valuable metals from waste NCM111 lithium-ion battery cathode material according to claim 1, characterized in that: Step (2) The solid-liquid ratio g:L of the waste battery positive electrode powder and the deep eutectic solvent is 20~50:1.